1. FIELD OF THE INVENTION
The present invention relates to an anti-lock control method for vehicles including the steps of estimating a vehicle speed by integrating the speed of a wheel, comparing the wheel speed with a reference value derived from such an estimated vehicle speed to judge whether or not a wheel is going into a locked condition and, when it is judged that the wheel is entering a locked condition, reducing a braking pressure to a wheel brake.
2. DESCRIPTION OF THE PRIOR ART
Such a method has been known, for example, from Japanese patent publication No. 47010/1981.
When a vehicle is traveling on a low friction road surface, i.e., on a road surface which creates a low level of friction between wheels of vehicles, wheels of the vehicle tend to be locked. Therefore, during travel of the vehicle on such a low friction road surface, it is desirable that the anti-lock control be carried out earlier than usual. The present inventors have found that, during braking of a vehicle traveling on a low friction road surface, the difference between a plurality of wheel speeds becomes large.